The headlines have already covered the basics. District 22 is moving out of Allegheny County altogether. There will have to be one last election for the remainder of the term there as incumbent Chelsea Wagner takes office as Allegheny County controller. The bigger surprise were all the incumbent Democrats being pushed into new districts. Current state house incumbents Adam Ravenstahl and Dom Costa appear to both be residents of a reformed District 21. Nick Kotik and Jesse White, districts 45 and 46 respectively, will have to run against each other if they choose to stay in the state house. Also Dan Deasy and Matt Smith appear to be residents of same district. Though talk is that Deasy being drawn a few blocks from his district, and Ravenstahl winding up a resident of 21 were actually something of administrative oversights and will be modified in the final plan. This all is technically just the preliminary plan.
For GIS wonks... The files used to create the maps below come from these files: SHP, DBF, PRJ, SBN, SBX. I'll get to the state senate geography when I can. Or if someone can make public the shapefiles used by the PLRC, that would certainly be more efficient.